Duplicating winners vs raising budget: the 20% rule still holds

Duplicating winners vs raising budget: the 20% rule still holds
Across 40 accounts, 90d, scaling a winning ad set:
— Raise budget >20%/day: re-enters learning, CPA spikes 30% for 2–3 days before settling
— Raise ≤20%/day: stays out of learning, CPA holds within 8%
— Duplicate to new ad set: fresh learning phase, only 40% of dupes match the original's CPA
Duplication resets the audience overlap and often cannibalizes the original. Incremental budget is the safer lever.
Read: scale winners with ≤20%/day budget bumps, not duplication. Dupes look clean but reset learning and overlap your own ads.